The present invention relates to an electric adapter comprised of two electric connectors mounted on a PC board at two opposite sides.
When connecting a PC board or conductive member between electric devices, electric connectors shall be used. FIG. 1 shows two electric connectors 11 and 12 mounted on one side of a PC board 10 at two opposite ends to form with the PC board 10 an electric adapter. This structure of electric adapter needs much installation space. FIG. 2 shows another structure of electric adapter according to the prior art, in which the PC board 13 has one end inserted in between the two rows of metal contacts 16 of a first electric connector 14 and an opposite end inserted in between the two rows of metal contacts 17 of a second electric connector 15. This structure of electric adapter cannot use circular electric connectors or any electric connector having three or more rows of metal contacts. FIG. 3 shows an electric adapter according to U.S. Pat. No. 4,618,196, which is the commercially available smallest electric adapter nowadays. However, the application range of this structure of electric adapter is limited. For example, a hole C must be made between two adjacent metal contacts A and B at one side for mounting a metal contact D at an opposite side. Because two metal contacts A and D cannot be simultaneously installed in a contact mounting hole on the PC board 18, all metal contacts at two opposite sides must not be aligned. Furthermore, regular electric adapters are made as small as possible in current markets. For example, in an SCSI electric adapter, the distance between the longitudinal central axes of two adjacent metal contacts is about 1.27 mm, and the pitch between two adjacent metal contacts is as narrow as 0.6 mm. Therefore, it is difficult to make a hole between two adjacent metal contacts.